Don't judge me

I've been in a new relationship with a guy for about a month and a half now. He's 8 years older, 3 kids and separated from his wife for 7 months now. Things have been stressful with him going through a divorce because she tries to cause us both hell. I expected the drama b4 getting into the relationship but the more I'm with him, the more I'm suspecting that he may not totally be over her yet because he keeps postponing the divorce/mediation meetings. And one night he told me he will always love her but knows he can't be with her. I told him that if he truly wants to be with me and says his marriage is over, I will support him but he must get the process started by the end of August because I can't be in this relationship wondering if he will ever actually divorce her which means I've wasted my time. When we first got together his mediation meeting was in 2 weeks but he cancelled it, and cancelled two other meetings that were rescheduled. It's obvious he has been delaying the process. I get that he will always love her as they were married 6 years and have 3 beautiful children together but he can't have the best of both world of having a wife and a girlfriend. My issue isn't the kids, it's him still treating her as his wife that he's together with even though he is with me. Almost as though I'm a rebound, although he says he's so in love with me & ive met most of his family. So I'm standing firm on my decision to leave him if he doesn't start his divorce process by the end of August. Which he is aware of and says it will get done. Since this is going on, I've made the decision to be a little distant in case I do need to walk away for good and so that it won't hurt as much when I have to do it. Problem is that I just found out I'm pregnant. 5 weeks. I told him, he is super happy as he says he loves me and is going to marry me one day, but that we can't tell his ex until the divorce is final...if it ever is final. I'm so worried. I can't have a baby by a man who's still married and whom I'm obviously worried won't get divorced. I feel terrible because I'm considering abortion. It's just really bad timing and I'm not certain of a future with him due to the circumstances. If he divorces her then great but I can't count on it actually happening because of the signs he has given me already. Some advice please!